MACROMEDIA Flash Lite 2, Reference

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Statements 189
Usage 4: The following example shows the behavior of
delete
on object references:
var ref1:Object = new Object();
ref1.name = "Jody";
// copy the reference variable into a new variable
// and delete ref1
ref2 = ref1;
delete ref1;
trace("ref1.name "+ref1.name); //output: ref1.name undefined
trace("ref2.name "+ref2.name); //output: ref2.name Jody
If
ref1
had not been copied into
ref2
, the object would have been deleted when
ref1
was
deleted because there would be no references to it. If you delete
ref2
, there are no references
to the object; it will be destroyed, and the memory it used becomes available.
See also
var statement
do..while statement
do { statement(s) } while ( condition )
Similar to a
while
loop, except that the statements are executed once before the initial
evaluation of the condition. Subsequently, the statements are executed only if the condition
evaluates to
true
.
A
do..while
loop ensures that the code inside the loop executes at least once. Although this
can also be done with a
while
loop by placing a copy of the statements to be executed before
the
while
loop begins, many programmers believe that
do..while
loops are easier to read.
If the condition always evaluates to
true
, the
do..while
loop is infinite. If you enter an
infinite loop, you encounter problems with Flash Player and eventually get a warning message
or crash the player. Whenever possible, you should use a
for
loop if you know the number of
times you want to loop. Although
for
loops are easy to read and debug, they cannot replace
do..while
loops in all circumstances.
Availability: ActionScript 1.0; Flash Lite 1.0
Parameters
condition : Boolean
- The condition to evaluate. The
statement(s)
within the
do
block of
code will execute as long as the
condition
parameter evaluates to
true
.